fix(multi): forward ConfigurationChanged events from child providers

openfeature/multi/multiprovider.go

@@ -118,7 +118,6 @@ var (
 func init() {
 	// used for mapping provider event types & provider states to comparable values for evaluation
 	stateValues = map[of.State]int{
-		"":            -1, // Not a real state, but used for handling provider config changes
 		of.ReadyState: 0,
 		of.StaleState: 1,
 		of.ErrorState: 2,
@@ -130,10 +129,9 @@ func init() {
 		of.ErrorState, // 2
 	}
 	eventTypeToState = map[of.EventType]of.State{
-		of.ProviderConfigChange: "",
-		of.ProviderReady:        of.ReadyState,
-		of.ProviderStale:        of.StaleState,
-		of.ProviderError:        of.ErrorState,
+		of.ProviderReady: of.ReadyState,
+		of.ProviderStale: of.StaleState,
+		of.ProviderError: of.ErrorState,
 	}
 }
 
@@ -483,6 +481,16 @@ func (p *Provider) forwardProviderEvents(workerCtx context.Context, handlers cha
 			slog.String(MetadataProviderType, e.ProviderName),
 		)
 		l.LogAttrs(workerCtx, slog.LevelDebug, "received event from provider", slog.String("event-type", string(e.EventType)))
+
+		// ConfigurationChanged events are always forwarded directly without affecting provider state tracking.
+		// This matches the JS SDK reference behavior where ConfigurationChanged is re-emitted as a direct
+		// pass-through, independent of status change logic.
+		if e.EventType == of.ProviderConfigChange {
+			p.outboundEvents <- e.Event
+			l.LogAttrs(workerCtx, slog.LevelDebug, "forwarded configuration changed event")
+			continue
+		}
+
 		if p.updateProviderStateFromEvent(e) {
 			p.outboundEvents <- e.Event
 			l.LogAttrs(workerCtx, slog.LevelDebug, "forwarded state update event")
@@ -509,10 +517,8 @@ func (p *Provider) updateProviderState(name string, state of.State) bool {
 
 // updateProviderStateFromEvent updates the state of an internal provider from an event emitted from it, and then
 // re-evaluates the overall state of the multiprovider. If this method returns true the overall state changed.
+// Note: ProviderConfigChange events are handled separately in forwardProviderEvents and never reach this method.
 func (p *Provider) updateProviderStateFromEvent(e namedEvent) bool {
-	if e.EventType == of.ProviderConfigChange {
-		p.logger.LogAttrs(context.Background(), slog.LevelDebug, "ProviderConfigChange event", slog.String("event-message", e.Message))
-	}
 	p.providerStatusLock.Lock()
 	previousState := p.providerStatus[e.providerName]
 	p.providerStatusLock.Unlock()

openfeature/multi/multiprovider_test.go

@@ -371,6 +371,93 @@ func TestMultiProvider_StateUpdateWithSameTypeProviders(t *testing.T) {
 	}
 }
 
+func TestMultiProvider_ConfigurationChangedEventForwarding(t *testing.T) {
+	// awaitEvent drains the outbound channel until an event of the given type is found.
+	awaitEvent := func(t *testing.T, ch <-chan of.Event, eventType of.EventType) of.Event {
+		t.Helper()
+		var found of.Event
+		require.Eventually(t, func() bool {
+			for {
+				select {
+				case e, ok := <-ch:
+					if !ok {
+						return false
+					}
+					if e.EventType == eventType {
+						found = e
+						return true
+					}
+				default:
+					return false
+				}
+			}
+		}, time.Second, 10*time.Millisecond, "expected %s event was not received", eventType)
+		return found
+	}
+
+	// setup creates a two-provider multi-provider, initializes it, and waits for READY.
+	setup := func(t *testing.T) (*Provider, *mockProviderWithEvents, *mockProviderWithEvents) {
+		t.Helper()
+		ctrl := gomock.NewController(t)
+		t.Cleanup(ctrl.Finish)
+
+		p1 := newMockProviderWithEvents(ctrl, "provider1")
+		p2 := newMockProviderWithEvents(ctrl, "provider2")
+
+		mp, err := NewProvider(
+			StrategyFirstMatch,
+			WithProvider("provider1", p1),
+			WithProvider("provider2", p2),
+		)
+		require.NoError(t, err)
+		t.Cleanup(mp.Shutdown)
+
+		require.NoError(t, mp.Init(of.NewEvaluationContext("test", nil)))
+		require.Eventually(t, func() bool {
+			return mp.Status() == of.ReadyState
+		}, time.Second, 10*time.Millisecond)
+
+		return mp, p1, p2
+	}
+
+	t.Run("event is forwarded with correct payload and does not corrupt provider state", func(t *testing.T) {
+		mp, provider1, _ := setup(t)
+
+		provider1.EmitEvent(of.ProviderConfigChange, "flags updated")
+		e := awaitEvent(t, mp.outboundEvents, of.ProviderConfigChange)
+
+		assert.Equal(t, "flags updated", e.Message)
+		assert.Equal(t, "provider1", e.EventMetadata[MetadataProviderName])
+
+		// Provider state should remain READY (not corrupted to empty string)
+		mp.providerStatusLock.Lock()
+		assert.Equal(t, of.ReadyState, mp.providerStatus["provider1"])
+		assert.Equal(t, of.ReadyState, mp.providerStatus["provider2"])
+		mp.providerStatusLock.Unlock()
+
+		assert.Equal(t, of.ReadyState, mp.Status())
+	})
+
+	t.Run("does not affect aggregate state when another provider is degraded", func(t *testing.T) {
+		mp, provider1, provider2 := setup(t)
+
+		// Put provider2 into STALE state
+		provider2.EmitEvent(of.ProviderStale, "stale")
+		awaitEvent(t, mp.outboundEvents, of.ProviderStale)
+		require.Equal(t, of.StaleState, mp.Status())
+
+		// ConfigurationChanged from provider1 should not affect aggregate
+		provider1.EmitEvent(of.ProviderConfigChange, "flags updated")
+		awaitEvent(t, mp.outboundEvents, of.ProviderConfigChange)
+
+		assert.Equal(t, of.StaleState, mp.Status())
+
+		mp.providerStatusLock.Lock()
+		assert.Equal(t, of.ReadyState, mp.providerStatus["provider1"])
+		mp.providerStatusLock.Unlock()
+	})
+}
+
 func TestMultiProvider_Track(t *testing.T) {
 	t.Run("forwards tracking to all ready providers that implement Tracker", func(t *testing.T) {
 		ctrl := gomock.NewController(t)